710
FXUS64 KEWX 191041 AAA
AFDEWX

Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
541 AM CDT Sat Apr 19 2025

...New AVIATION (12Z TAFS)...

.SHORT TERM...
(Today through Sunday)
Issued at 150 AM CDT Sat Apr 19 2025

Key Messages:

- There is a Level 1 of 5 risk for Severe Thunderstorms during the
  ongoing overnight hours across the Southern Edwards Plateau.

- There is a Level 1 to 2 of 5 Risk for Severe Thunderstorms later
  today through early Easter Morning, generally along and west of
  the I-35 Corridor.

An active short term period is expected for South Central Texas. The
latest GOES 19 Water Vapor imagery shows a compact upper level low
over northern Arizona. Out ahead of the low, a 50-70 kt 500mb jet is
situated over west Texas. Strong diffluence aloft will help to
ventilate any convection that forms overnight, particularly in an
environment that`s been largely capped the past couple of days. It
won`t take long for storms to grow upscale in an environment
characterized by MLCAPE values in the 2000-3000 J/kg range, ML Lapse
rates of 8-9 C/km, and 0-6km bulk shear in the 60-70 kt range.
Storms have already fired up over the northern Rio Grande Plains and
Edwards Plateau and based off of the latest regional radar imagery
and are expected to continue sliding north and east. Most of this
activity should remain west of I-35, but if the latest 06Z CAMs are
to be believed, some storms may make it as far east as the Hill
Country.

There should be a lull in storm coverage from shortly after
sunrise through midday before potentially seeing some supercells
develop over the Rio Grande Plains and Edwards Plateau early
afternoon and move east. At this time, we do not think any
supercellular activity will make it far enough east to impact the I-
35 Corridor but we will have to watch convection as it develops late
tomorrow evening over the Edwards Plateau and slides east with a
frontal boundary Saturday night into Sunday morning. Storms may be
severe initially as SPC has a level 1 to 2 of 5 risk in place for
areas west of I-35, but storms should weaken as the push east into
the I-35 Corridor around sunrise Easter morning. Some redevelopment
is possible in the afternoon over the Coastal Plains, but severe
storms should remain east of our area. Temperatures will certainly be
cooler and things should dry out for the afternoon Sunday with highs
in the 70s and 80s.

&&

.LONG TERM...
(Sunday night through Friday)
Issued at 150 AM CDT Sat Apr 19 2025

Key Messages:

- Daily rain and thunderstorm chances middle to late next week

- Becomes increasingly humid with slightly above average warmth

The front that advances through the region on Easter Sunday will
slow down and stall along the Texas gulf coast Sunday night through
Monday. This will promote a lingering rain and storm chance across
our coastal plain counties closest to the stalled boundary. Rain
free conditions are expected elsewhere through Monday night under
partly cloudy to mostly clear skies and a light east-northeast flow.
The front lifts back northward as a warm front into early Tuesday
morning with winds returning out of the southeast.

An active southwesterly mid-level flow pattern will be in place for
midweek onward through at least the start of next weekend. Several
embedded shortwaves within the flow will advance into and through
the region. This and a warm, humid low-level airmass with above
average precipitable water values will promote daily chances for
rain and thunderstorms through the region. Convective outflows and
terrain induced convection off Mexico could also factor into the
chances next week. Returning instability each day and sufficient
deep layer shear at times could allow for some organized stronger
thunderstorms at times. As the pattern evolves, we`ll refine the
windows for rain and thunderstorm chances. Thunderstorms will
produce locally heavy rain at times. While the greatest rainfall
footprint through next week will likely favor areas farther north,
there is a medium to high (40 to 80 percent) probability for at
least 1 inch of rainfall on average in the region with localized
higher amounts of 2+ inches in locations where the heaviest
thunderstorms do occur.

Temperatures will remain slightly above average despite increased
humidity and cloud cover mid to late week. Afternoon nights are
still expected to climb into the 80s for most locations most days
while the Rio Grande could eclipse 90 degrees at times. Monday
likely will be the warmest day with the least cloud cover. Muggy
nights are expected, especially midweek onward, with overnight
lows up into the mid to upper 60s area wide.

&&

.AVIATION...
(12Z TAFS)
Issued at 521 AM CDT Sat Apr 19 2025

The primary concern in this TAF cycle will be the threat of
convection at area terminals. Despite lower confidence, will hold
onto PROB30 groups this afternoon through early evening at AUS, SAT,
and SSF and introduce a second PROB30 group after 6am Sunday at these
same sites. At DRT, opted for a TEMPO between 04-07Z Sunday to
account for greater coverage and confidence in storms. A frontal
boundary will move through by mid-morning Sunday, so have introduced
westerly to northwesterly winds behind it at AUS and SAT.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              86  67  81  59 /  40  30  70  10
Austin Bergstrom Intl Airport  86  66  80  57 /  40  30  70  10
New Braunfels Muni Airport     86  67  82  59 /  40  20  70  10
Burnet Muni Airport            84  64  78  56 /  50  60  60  10
Del Rio Intl Airport           90  65  85  60 /  30  70  10   0
Georgetown Muni Airport        84  65  80  56 /  40  40  70  10
Hondo Muni Airport             87  64  83  57 /  30  50  50  10
San Marcos Muni Airport        86  67  80  58 /  40  20  70  10
La Grange - Fayette Regional   86  70  82  63 /  20  10  70  30
San Antonio Intl Airport       86  68  81  61 /  30  30  70  10
Stinson Muni Airport           88  69  81  62 /  30  30  70  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

Short-Term...MMM
Long-Term...Brady
Aviation...MMM